Portion of a brush



FIG. 1 is a front left perspective view of a portion of a brush showingour new design;

FIG. 2 is a right side view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a front view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a rear right perspective view thereof.

The dash-dot-dash broken lines immediately adjacent to the shaded areasrepresent unclaimed boundaries of the claimed design. The dotted brokenlines are for illustrative purposes only and form no part of the claimeddesign.

The ornamental design for a portion of a brush, as shown and described.